Evaluation of using two metabolites of Vitamin D3 with phytase in the diet of laying hens finishing their productive cycle

摘要

The effect of supplementing the diet with two sources of vitamin Dsub>3, 1α-hidroxycholecalciferol (1α-OH-D3) and 25-hidroxycholecalciferol (25-OH-D3), in the presence of phytase, on the productive indicators, the bone mineral composition and the external quality of the eggs of comercial laying hens during weeks 55 to 68 of life. A total of 360 Lohman Brown hens were used, distributed between four treatments with six replicates per treatment and 15 birds per replicate. The diets were: T1 (diet with 50g ton-1 of phytose), T2 (same as T1 plus 12.5g ton-1 of 1α-OH-D3 without considering the phosphorus and calcium contributions), T3 (same as T1 with the addition of 12. 5g ton-1 considering a liberation of 0.05% of available phosphorus and calcium ), and T4 (same as T1 with the addition of 5.52g ton-1 of 25-OH-D3 considering a liberation of 0.05% of available phosphorus and calcium). All birds had free Access to wáter and food according to recomendations for comercial lines. The variables laying percentage, cumulative conversión, egg quality, Shell minerals, percentage of Shell in the egg, egg density, and bone minerals were not significantly influenced (p>0.05) by the source or type of inclusión of vitamin D3. However, the use of vitamin 1α-OH-D3 in a matrix showed a net economic benefit, representing the lowest production cost and highest income for egg sales. In future research with laying hens, it is necessary to check the level of inclusión of vitamin D3 as well as the concentration of calcium in the diet.